Proprioception, muscle mass, and strength are o ten impaired in patients with osteoarthritis (OA). Use of a neoprene sleeve has been reported to improve proprioception in both normal and arthritic patients. Other braces have been marketed to relieve pain by mechanically unloading an arthritic knee compartment, thereby providing the advantages of realignment osteotomy without the surgical risk or expense. However, the effect of these braces on proprioception is unknown. The substantial difference in cost between a neoprene sleeve and custom unloading brace may be justified if it significantly improves proprioception and knee stability. Often, high tibial osteotomy (HTO) surgery is performed in patients with medial compartment OA to correct mechanical alignment, alleviate pain, and restore function. The objective of this study is to evaluate the effects of two braces (i.e., neoprene sleeve and medial unloader brace) as well as surgical correction of lower limb deformity with HTO. A prospective study of these treatment options will be undertaken to assess neuromuscular function in patients with unilateral medial compartment OA of the knee. Twenty patients between 30 and 55 years of age who have consented to receive HTO surgery will be recruited. Physical and radiographic exams will be evaluated pre- and post-operatively, along with validated patient outcome measures. Assessments of neuromuscular function will be made pre-operatively and at 6 months post-operatively, both without bracing and while wearing a neoprene sleeve and a medial unloader brace. The effects of each brace on neuromuscular function will be tested by measuring four dependent variables: 1) Proprioception (i.e., ability to detect passive motion and reproduce active/passive positioning); 2) Electromyographic activity of the quadriceps during treadmill walking; 3) Balance testing during single leg stance; and 4) Isokinetic strength testing of the quadriceps and hamstring muscles. The relationship between alleviating pain and neuromuscular function will also be assessed using validated outcome measures and visual-analogue pain scales. it is hypothesized that bracing and HTO will significantly improve proprioception, quadriceps muscle activity, balance and strength compared to the unbraced knee condition. Of these treatments, HTO is anticipated to provide the greatest improvements in pain and neuromuscular function. By comparing the effects of the neoprene sleeve, and the medial unloader brace, both before after HTO surgery, we will obtain insight on the effects of bracing and a greater understanding of the role of HTO in the treatment of medial compartment OA. Furthermore, the effect of pain alleviation on knee proprioception following treatment has not been explored. Understanding the effect of braces and surgical realignment on this important relationship should have significant implications for the treatment and rehabilitation of these patients.